Add dedicated FlashInferCuteDslMoE layer for standard-path FP4 MoE (#21339)

This commit is contained in:
Lee Nau
2026-04-10 01:35:56 -07:00
committed by GitHub
parent 7c6b5c095c
commit c554dc5c64
8 changed files with 1252 additions and 187 deletions
@@ -0,0 +1,353 @@
from __future__ import annotations
import logging
from dataclasses import dataclass
from typing import TYPE_CHECKING, Any
import torch
from sglang.srt.layers.moe.moe_runner.base import (
MoeQuantInfo,
MoeRunnerConfig,
register_fused_func,
)
from sglang.srt.utils.common import log_info_on_rank0, print_warning_once
if TYPE_CHECKING:
from sglang.srt.layers.moe.token_dispatcher import (
StandardCombineInput,
StandardDispatchOutput,
)
logger = logging.getLogger(__name__)
_FP4_SF_VEC_SIZE = 16
_cutedsl_logged_scalarize: set = set()
# ---------------------------------------------------------------------------
# Weight / scale preparation utilities (called from modelopt_quant.py during
# process_weights_after_loading and lazy wrapper init)
# ---------------------------------------------------------------------------
def interleave_w13_halves(
tensor: torch.Tensor, group_size: int = 64, dim: int = 1
) -> torch.Tensor:
"""Interleave the two logical W13 halves for CuteDSL's SwiGLU GEMM1 layout.
The caller is responsible for loading W13 in the expected two-half order.
This helper only rewrites the first and second halves into alternating
`group_size` chunks along `dim`.
"""
if tensor.shape[dim] % 2 != 0:
raise ValueError(
"Expected even size on interleave dimension for W13 half split."
)
split = tensor.shape[dim] // 2
if split % group_size != 0:
raise ValueError(
f"Expected split dim divisible by group_size={group_size}, got {split}."
)
first_half = tensor.narrow(dim, 0, split)
second_half = tensor.narrow(dim, split, split)
first_half_groups = first_half.split(group_size, dim=dim)
second_half_groups = second_half.split(group_size, dim=dim)
interleaved = [
item for pair in zip(first_half_groups, second_half_groups) for item in pair
]
return torch.cat(interleaved, dim=dim)
def cutedsl_quant_scale_to_scalar(
quant_scale: torch.Tensor,
*,
name: str,
) -> torch.Tensor:
"""Reduce per-expert quant-domain scale vector to a single scalar.
The quant domain is the reciprocal of the raw checkpoint scale:
quant_scale = 1 / raw_scale
Returns min(quant_scale) = 1/max(raw_scale), which is the TRTLLM CuteDSL
convention for global scalar activation scales (see TRTLLM quantization.py
lines 2137-2141: fc2_input_scale = tmp_fc2_input_scale.max().reciprocal()).
If quant_scale is already scalar (numel==1), returns it unchanged.
"""
quant_scale = quant_scale.to(torch.float32)
if quant_scale.numel() == 0:
print_warning_once(
f"CuteDSL got empty {name}; using 1.0 fallback.",
)
return torch.ones(1, device=quant_scale.device, dtype=torch.float32)
if quant_scale.numel() == 1:
return quant_scale.reshape(1)
if name not in _cutedsl_logged_scalarize:
log_info_on_rank0(
logger,
f"CuteDSL: reducing per-expert {name} to scalar via "
"min(quant_scale) = 1/max(raw_scale), matching TRTLLM convention.",
)
_cutedsl_logged_scalarize.add(name)
return quant_scale.min().reshape(1)
def resolve_cutedsl_standard_scales(
layer: torch.nn.Module,
) -> tuple[torch.Tensor, torch.Tensor, torch.Tensor, torch.Tensor]:
"""Resolve standard-path CuteDSL scales (baseline: scalar fc2/w13 input scales).
Returns (w1_alpha, fc2_input_scale, w2_alpha, used_input_scale).
used_input_scale is the scalarized w13 input scale for FP4 quantize and GEMM1.
"""
def _to_fp32_tensor(x: torch.Tensor | float, ref: torch.Tensor) -> torch.Tensor:
if not isinstance(x, torch.Tensor):
x = torch.tensor(x, device=ref.device)
return x.to(device=ref.device, dtype=torch.float32)
def _align_scale_to_alpha(
scale: torch.Tensor, alpha: torch.Tensor, scale_name: str
) -> torch.Tensor:
scale = scale.to(device=alpha.device, dtype=torch.float32)
alpha = alpha.to(torch.float32)
if scale.ndim == 0:
return scale
# Gated weight scales may be (num_experts, 2) with separate gate/up
# columns. Collapse to 1D by taking the first column (gate == up for
# well-formed checkpoints; mismatch is warned in process_weights_after_loading).
if scale.ndim == 2 and scale.shape[1] <= 2:
scale = scale[:, 0]
if scale.numel() == alpha.numel():
return scale
if scale.numel() == 1:
return scale.reshape(())
# Some EP setups may carry global-per-expert scale vectors while alphas are
# local-per-expert vectors. Slice to this rank's local expert range.
num_local_experts = getattr(layer, "num_local_experts", None)
num_experts = getattr(layer, "num_experts", None)
moe_ep_rank = getattr(layer, "moe_ep_rank", 0)
if (
num_local_experts is not None
and num_experts is not None
and scale.numel() == num_experts
and alpha.numel() == num_local_experts
):
start = moe_ep_rank * num_local_experts
end = start + num_local_experts
return scale[start:end]
raise ValueError(
f"Unable to align {scale_name} shape={tuple(scale.shape)} "
f"to alpha shape={tuple(alpha.shape)} for CuteDSL standard scale resolution."
)
def _resolve_w1_alpha_from_scalar_input_scale(
used_input_scale: torch.Tensor,
) -> torch.Tensor:
"""Resolve GEMM1 alpha consistent with scalarized activation quant scale.
CuteDSL pre-quantizes x with a single scalar (used_input_scale), but
g1_alphas was derived with per-expert activation scales:
g1_alphas[e] = (1/w13_isq[e]) * w13_ws2[e]
Correct alpha for scalar quantization:
w1_alpha[e] = w13_ws2[e] / used_input_scale
= g1_alphas[e] * w13_isq[e] / used_input_scale
When w13_isq is already scalar, this is a no-op (ratio = 1).
"""
eps = 1e-12
scalar = torch.clamp(used_input_scale.to(torch.float32).reshape(()), min=eps)
if hasattr(layer, "w13_weight_scale_2"):
w13_weight_scale_2 = _align_scale_to_alpha(
layer.w13_weight_scale_2, layer.g1_alphas, "w13_weight_scale_2"
)
return w13_weight_scale_2.to(torch.float32) / scalar
w13_isq = _align_scale_to_alpha(
layer.w13_input_scale_quant, layer.g1_alphas, "w13_input_scale_quant"
)
w13_isq = torch.clamp(_to_fp32_tensor(w13_isq, layer.g1_alphas), min=eps)
return (layer.g1_alphas.to(torch.float32) * w13_isq / scalar).to(torch.float32)
def _resolve_w2_alpha_from_scalar_fc2_input_scale(
fc2_input_scale: torch.Tensor,
) -> torch.Tensor:
"""Resolve GEMM2 alpha consistent with scalarized FC2 input scale.
CuteDSL standard path uses a scalar global scale for GEMM1 FP4 output
quantization (`fc2_input_scale`). GEMM2 alpha must use the same scalar
convention: alpha2 = w2_weight_scale_2 / fc2_input_scale.
"""
eps = 1e-12
fc2_input_scale = fc2_input_scale.to(torch.float32)
fc2_scalar = torch.clamp(fc2_input_scale.reshape(-1)[:1], min=eps).reshape(())
if hasattr(layer, "w2_weight_scale_2"):
w2_weight_scale_2 = _align_scale_to_alpha(
layer.w2_weight_scale_2, layer.g2_alphas, "w2_weight_scale_2"
)
w2_weight_scale_2 = w2_weight_scale_2.to(torch.float32)
return w2_weight_scale_2 / fc2_scalar
w2_q_for_w2 = _align_scale_to_alpha(
layer.w2_input_scale_quant, layer.g2_alphas, "w2_input_scale_quant"
)
w2_q_for_w2 = torch.clamp(
_to_fp32_tensor(w2_q_for_w2, layer.g2_alphas), min=eps
)
w2_weight_scale_2 = layer.g2_alphas.to(torch.float32) * w2_q_for_w2
return w2_weight_scale_2 / fc2_scalar
fc2_input_scale = cutedsl_quant_scale_to_scalar(
layer.w2_input_scale_quant,
name="w2_input_scale_quant",
)
w2_alpha = _resolve_w2_alpha_from_scalar_fc2_input_scale(fc2_input_scale)
used_input_scale = cutedsl_quant_scale_to_scalar(
layer.w13_input_scale_quant,
name="w13_input_scale_quant",
)
w1_alpha = _resolve_w1_alpha_from_scalar_input_scale(used_input_scale)
return w1_alpha, fc2_input_scale, w2_alpha, used_input_scale
def ensure_cutedsl_wrapper(layer: torch.nn.Module) -> None:
"""Lazily create CuteDslMoEWrapper and resolve scales on first forward.
The wrapper is created lazily (not in __init__ / create_weights) because
it depends on final weight shapes and EP configuration. The wrapper's
CUDA-graph buffers are allocated inside CuteDslMoEWrapper.__init__, which
typically runs during the autotune dummy forward under inference_mode().
We wrap the creation in inference_mode(False) so that those pre-allocated
buffers are normal tensors -- inference tensors cannot be inplace-updated
during later CUDA graph capture, which runs outside inference_mode.
"""
if getattr(layer, "_cutedsl_wrapper", None) is not None:
return
try:
from flashinfer import CuteDslMoEWrapper
except ImportError as e:
raise ImportError(
"flashinfer_cutedsl backend requires FlashInfer with CuteDSL support. "
"Install with: pip install flashinfer"
) from e
from sglang.srt.server_args import get_global_server_args
assert layer.intermediate_size_per_partition > 0, (
f"CuteDSL MoE: intermediate_size_per_partition must be > 0, "
f"got {layer.intermediate_size_per_partition}. Check EP/TP configuration."
)
server_args = get_global_server_args()
use_cuda_graph = server_args is not None and not server_args.disable_cuda_graph
max_num_tokens = max(
getattr(server_args, "cuda_graph_max_bs", None) or 512,
getattr(server_args, "chunked_prefill_size", None) or 8192,
)
top_k = layer.top_k if layer.top_k is not None else layer.moe_runner_config.top_k
# inference_mode(False) ensures the wrapper's pre-allocated CUDA-graph
# buffers are normal tensors. This call typically happens inside
# _dummy_run which runs under inference_mode(); inference tensors cannot
# be inplace-updated during later CUDA graph capture (which runs outside
# inference_mode), so we must opt out here.
with torch.inference_mode(False):
layer._cutedsl_wrapper = CuteDslMoEWrapper(
num_experts=layer.num_experts,
top_k=top_k,
hidden_size=layer.hidden_size,
intermediate_size=layer.intermediate_size_per_partition,
use_cuda_graph=use_cuda_graph,
max_num_tokens=max_num_tokens,
num_local_experts=layer.num_local_experts,
local_expert_offset=layer.moe_ep_rank * layer.num_local_experts,
output_dtype=layer.moe_runner_config.params_dtype,
device=str(layer.w13_weight.device),
)
w1_alpha, fc2_input_scale, w2_alpha, used_input_scale = (
resolve_cutedsl_standard_scales(layer)
)
layer._cutedsl_scales = (w1_alpha, fc2_input_scale, w2_alpha)
layer._cutedsl_input_scale = used_input_scale
# ---------------------------------------------------------------------------
# Dataclass + fused function for moe_runner dispatch
# ---------------------------------------------------------------------------
@dataclass
class CuteDslFp4MoeQuantInfo(MoeQuantInfo):
"""Quantization payload consumed by FlashInfer CuteDSL FP4 MoE kernels."""
# Lazily-created CuteDslMoEWrapper (stashed on layer)
wrapper: Any
# Weights (uint8 FP4 packed)
w13_weight: torch.Tensor
w2_weight: torch.Tensor
# Block-scale factors
w13_weight_sf: torch.Tensor
w2_weight_sf: torch.Tensor
# Per-expert GEMM scales
w1_alpha: torch.Tensor
w2_alpha: torch.Tensor
# Intermediate quantization scale (fc2 input)
fc2_input_scale: torch.Tensor
# Activation quantization scale (scalarized)
input_scale: torch.Tensor
@register_fused_func("none", "flashinfer_cutedsl")
def fused_experts_none_to_flashinfer_cutedsl_fp4(
dispatch_output: StandardDispatchOutput,
quant_info: CuteDslFp4MoeQuantInfo,
runner_config: MoeRunnerConfig,
) -> StandardCombineInput:
from flashinfer import fp4_quantize
from sglang.srt.layers.moe.token_dispatcher.standard import StandardCombineInput
from sglang.srt.layers.moe.topk import TopKOutputChecker
assert runner_config.activation == "silu", "Only silu is supported for CuteDSL MoE."
hidden_states = dispatch_output.hidden_states
topk_output = dispatch_output.topk_output
assert TopKOutputChecker.format_is_standard(topk_output)
topk_ids = topk_output.topk_ids
topk_weights = topk_output.topk_weights
if topk_ids.dtype != torch.int32:
topk_ids = topk_ids.to(torch.int32)
x_fp4, x_sf = fp4_quantize(
hidden_states,
quant_info.input_scale,
sf_vec_size=_FP4_SF_VEC_SIZE,
is_sf_swizzled_layout=False,
)
output = quant_info.wrapper.run(
x=x_fp4,
x_sf=x_sf,
token_selected_experts=topk_ids,
token_final_scales=topk_weights,
w1_weight=quant_info.w13_weight,
w1_weight_sf=quant_info.w13_weight_sf,
w1_alpha=quant_info.w1_alpha,
fc2_input_scale=quant_info.fc2_input_scale,
w2_weight=quant_info.w2_weight,
w2_weight_sf=quant_info.w2_weight_sf,
w2_alpha=quant_info.w2_alpha,
)
return StandardCombineInput(hidden_states=output)
@@ -54,6 +54,8 @@ class MoeRunner:
or runner_backend.is_flashinfer_trtllm_routed()
):
self.runner_core = None # FlashInfer TRT-LLM only supports fused path
elif runner_backend.is_flashinfer_cutedsl():
self.runner_core = None # FlashInfer CuteDSL only supports fused path
else:
raise NotImplementedError(f"Unsupported runner backend: {runner_backend}")
@@ -88,8 +88,14 @@ class StandardDispatcher(BaseDispatcher):
def __init__(self, moe_runner_config: MoeRunnerConfig):
super().__init__()
self.moe_ep_size = get_moe_expert_parallel_world_size()
self.enable_flashinfer_cutlass_moe = (
get_moe_runner_backend().is_flashinfer_cutlass()
backend = get_moe_runner_backend()
self.enable_flashinfer_cutlass_moe = backend.is_flashinfer_cutlass()
# FlashInfer CUTLASS and CuteDSL handle EP internally with global expert IDs.
# Skip local expert mapping so topk_ids stay in global space.
self.skip_local_expert_mapping = (
backend.is_flashinfer_cutlass()
or backend.is_flashinfer_cutedsl()
or backend.is_flashinfer_trtllm_routed()
)
self.enable_flashinfer_trtllm_routed_moe = (
get_moe_runner_backend().is_flashinfer_trtllm_routed()
@@ -149,8 +155,7 @@ class StandardDispatcher(BaseDispatcher):
if (
self.moe_ep_size > 1
and not self.enable_flashinfer_cutlass_moe
and not self.enable_flashinfer_trtllm_routed_moe
and not self.skip_local_expert_mapping
and TopKOutputChecker.format_is_standard(topk_output)
):
if self.local_expert_mapping is None:
@@ -51,7 +51,6 @@ from sglang.srt.layers.quantization.utils import (
from sglang.srt.layers.radix_attention import RadixAttention
from sglang.srt.layers.utils import copy_or_rebind_param
from sglang.srt.utils.common import (
get_bool_env_var,
is_cuda,
is_sm120_supported,
next_power_of_2,
@@ -167,10 +166,6 @@ if is_cuda() and (not is_sm120_supported()) and (fp4_quantize is not None):
return
CUTEDSL_MOE_SCALAR_INPUT_SCALE = get_bool_env_var(
"SGLANG_CUTEDSL_MOE_SCALAR_INPUT_SCALE", "true"
)
# FP4 GEMM alignment constant - CUTLASS/FlashInfer kernels require dimensions divisible by 32
FP4_GEMM_ALIGNMENT = 32
@@ -993,9 +988,10 @@ class ModelOptFp8MoEMethod(FusedMoEMethodBase):
) -> CombineInput:
x = dispatch_output.hidden_states
topk_output = dispatch_output.topk_output
from sglang.srt.layers.moe.token_dispatcher import StandardCombineInput
from sglang.srt.layers.moe.topk import TopKOutputChecker
# Fast path: TRT-LLM FP8 per-tensor MoE using BYPASSED TopK routing
from sglang.srt.layers.moe.topk import TopKOutputChecker
if (
get_moe_runner_backend().is_flashinfer_trtllm()
@@ -1089,8 +1085,6 @@ class ModelOptFp8MoEMethod(FusedMoEMethodBase):
activation_type=activation,
)[0]
from sglang.srt.layers.moe.token_dispatcher import StandardCombineInput
return StandardCombineInput(hidden_states=output)
quant_info = TritonMoeQuantInfo(
@@ -1547,9 +1541,9 @@ class ModelOptNvFp4FusedMoEMethod(FusedMoEMethodBase):
@property
def enable_flashinfer_cutedsl_moe(self) -> bool:
"""Access the global enable_flashinfer_cutedsl_moe setting."""
from sglang.srt.layers.moe import get_moe_runner_backend
"""Access the global enable_flashinfer_cutedsl_moe setting."""
return get_moe_runner_backend().is_flashinfer_cutedsl()
def create_weights(
@@ -1714,19 +1708,12 @@ class ModelOptNvFp4FusedMoEMethod(FusedMoEMethodBase):
w13_input_scale = layer.w13_input_scale.max().to(torch.float32)
w2_input_scale = layer.w2_input_scale.max().to(torch.float32)
elif self.enable_flashinfer_cutedsl_moe:
# All-expert-one-input-scale is mathematically different from default per-expert-input-scale
# Thus we allow users to switch the flag to do thorough testing
if CUTEDSL_MOE_SCALAR_INPUT_SCALE:
w13_input_scale = (
layer.w13_input_scale.max()
.to(torch.float32)
.repeat(layer.w13_input_scale.shape[0])
)
else:
w13_input_scale = layer.w13_input_scale.max(dim=1).values.to(
torch.float32
)
# CuteDSL standard path uses a single scalar input scale (all experts).
w13_input_scale = (
layer.w13_input_scale.max()
.to(torch.float32)
.repeat(layer.w13_input_scale.shape[0])
)
w2_input_scale = layer.w2_input_scale
def _slice_scale(w):
@@ -1825,6 +1812,26 @@ class ModelOptNvFp4FusedMoEMethod(FusedMoEMethodBase):
else:
# CUTLASS processing - handle w13 and w2 separately
if self.enable_flashinfer_cutedsl_moe and layer.moe_runner_config.is_gated:
# For the CuteDSL FP4 path, interleave the two logical W13 halves
# in 64-row chunks before swizzling the block-scales.
from sglang.srt.layers.moe.moe_runner.flashinfer_cutedsl import (
interleave_w13_halves,
)
layer.w13_weight = Parameter(
interleave_w13_halves(
layer.w13_weight.view(torch.uint8), group_size=64, dim=1
).contiguous(),
requires_grad=False,
)
layer.w13_weight_scale = Parameter(
interleave_w13_halves(
layer.w13_weight_scale, group_size=64, dim=1
).contiguous(),
requires_grad=False,
)
# Process w13 weights
w13_blockscale_swizzled = swizzle_blockscale(layer.w13_weight_scale)
copy_or_rebind_param(
@@ -1869,6 +1876,45 @@ class ModelOptNvFp4FusedMoEMethod(FusedMoEMethodBase):
layer, "w2_blockscale_swizzled", w2_blockscale_swizzled
)
if self.enable_flashinfer_cutedsl_moe:
# CuteDSL expects MMA layout for weight scales. Convert from swizzled bytes.
from flashinfer.cute_dsl.utils import convert_sf_to_mma_layout
from sglang.srt.layers.moe.moe_runner.flashinfer_cutedsl import (
_FP4_SF_VEC_SIZE,
)
sf_vec_size = _FP4_SF_VEC_SIZE
num_local_experts = layer.w13_weight.shape[0]
w13_m = layer.w13_weight.shape[1]
w13_k = layer.w13_weight.shape[2] * 2
w2_m = layer.w2_weight.shape[1]
w2_k = layer.w2_weight.shape[2] * 2
layer.w13_blockscale_mma = Parameter(
convert_sf_to_mma_layout(
layer.w13_blockscale_swizzled.contiguous()
.view(torch.uint8)
.reshape(-1),
m=w13_m,
k=w13_k,
num_groups=num_local_experts,
sf_vec_size=sf_vec_size,
),
requires_grad=False,
)
layer.w2_blockscale_mma = Parameter(
convert_sf_to_mma_layout(
layer.w2_blockscale_swizzled.contiguous()
.view(torch.uint8)
.reshape(-1),
m=w2_m,
k=w2_k,
num_groups=num_local_experts,
sf_vec_size=sf_vec_size,
),
requires_grad=False,
)
# Both flashinfer cutlass and regular cutlass use same processing for w2
# Set up CUTLASS MoE parameters (reuse to keep CUDA graph stable)
@@ -1894,27 +1940,34 @@ class ModelOptNvFp4FusedMoEMethod(FusedMoEMethodBase):
@property
def load_up_proj_weight_first(self) -> bool:
# FlashInfer CUTLASS kernel assumes [Up, Gate] Proj as W13
return self.enable_flashinfer_cutlass_moe and self.moe_runner_config.is_gated
# Load W13 as [Up, Gate] for FlashInfer CUTLASS/CuteDSL kernels.
return self.moe_runner_config.is_gated and (
self.enable_flashinfer_cutlass_moe or self.enable_flashinfer_cutedsl_moe
)
def create_moe_runner(
self, layer: torch.nn.Module, moe_runner_config: MoeRunnerConfig
):
self.moe_runner_config = moe_runner_config
if get_moe_runner_backend().is_flashinfer_trtllm():
self.runner = MoeRunner(
MoeRunnerBackend.FLASHINFER_TRTLLM, moe_runner_config
)
elif get_moe_runner_backend().is_flashinfer_trtllm_routed():
self.runner = MoeRunner(
MoeRunnerBackend.FLASHINFER_TRTLLM_ROUTED, moe_runner_config
)
moe_runner_backend = get_moe_runner_backend()
if moe_runner_backend.is_auto():
# TRTLLM is currently the most performant and tested FP4 MoE
# backend, so use it as the default.
moe_runner_backend = MoeRunnerBackend.FLASHINFER_TRTLLM
if moe_runner_backend.is_flashinfer_cutedsl():
import sglang.srt.layers.moe.moe_runner.flashinfer_cutedsl # noqa: F401 triggers @register_fused_func
if not moe_runner_backend.is_flashinfer_cutlass():
self.runner = MoeRunner(moe_runner_backend, moe_runner_config)
def apply(
self,
layer: FusedMoE,
dispatch_output: StandardDispatchOutput,
) -> CombineInput:
from sglang.srt.layers.moe.token_dispatcher import StandardCombineInput
x = dispatch_output.hidden_states
x_sf = dispatch_output.hidden_states_scale
@@ -1958,6 +2011,33 @@ class ModelOptNvFp4FusedMoEMethod(FusedMoEMethodBase):
return self.runner.run(dispatch_output, quant_info)
if self.enable_flashinfer_cutedsl_moe:
from sglang.srt.layers.moe.moe_runner.flashinfer_cutedsl import (
CuteDslFp4MoeQuantInfo,
ensure_cutedsl_wrapper,
)
ensure_cutedsl_wrapper(layer)
w1_alpha, fc2_input_scale, w2_alpha = layer._cutedsl_scales
w1_weight_sf = getattr(
layer, "w13_blockscale_mma", layer.w13_blockscale_swizzled
)
w2_weight_sf = getattr(
layer, "w2_blockscale_mma", layer.w2_blockscale_swizzled
)
quant_info = CuteDslFp4MoeQuantInfo(
wrapper=layer._cutedsl_wrapper,
w13_weight=layer.w13_weight,
w2_weight=layer.w2_weight,
w13_weight_sf=w1_weight_sf,
w2_weight_sf=w2_weight_sf,
w1_alpha=w1_alpha,
w2_alpha=w2_alpha,
fc2_input_scale=fc2_input_scale,
input_scale=layer._cutedsl_input_scale,
)
return self.runner.run(dispatch_output, quant_info)
if self.enable_flashinfer_cutlass_moe:
from sglang.srt.layers.moe.token_dispatcher import DispatchOutputChecker
@@ -1997,7 +2077,7 @@ class ModelOptNvFp4FusedMoEMethod(FusedMoEMethodBase):
fc2_expert_weights=layer.w2_weight.view(torch.long),
output_dtype=output_dtype,
input_sf=x_sf,
# swizzled_input_sf=not get_moe_a2a_backend().is_flashinfer(),
# swizzled_input_sf intentionally omitted; not used for this path.
quant_scales=[
layer.w13_input_scale_quant,
layer.w13_blockscale_swizzled.view(torch.int32),
@@ -2015,8 +2095,6 @@ class ModelOptNvFp4FusedMoEMethod(FusedMoEMethodBase):
enable_alltoall=get_moe_a2a_backend().is_flashinfer(),
)[0]
from sglang.srt.layers.moe.token_dispatcher import StandardCombineInput
return StandardCombineInput(hidden_states=output)
from sglang.srt.layers.moe.cutlass_moe import cutlass_moe_fp4
@@ -2038,8 +2116,6 @@ class ModelOptNvFp4FusedMoEMethod(FusedMoEMethodBase):
apply_router_weight_on_input=moe_runner_config.apply_router_weight_on_input,
).to(x.dtype)
# Scale by routed_scaling_factor is fused into select_experts.
from sglang.srt.layers.moe.token_dispatcher import StandardCombineInput
return StandardCombineInput(hidden_states=output)
def apply_without_routing_weights(
@@ -2148,6 +2148,7 @@ class ModelRunner(ModelRunnerKVCacheMixin):
# TODO: Enable for flashinfer_trtllm_routed once https://github.com/flashinfer-ai/flashinfer/issues/2749 is fixed.
# "flashinfer_trtllm_routed",
"flashinfer_mxfp4",
"flashinfer_cutedsl",
# TODO: flashinfer_cutlass will cause some flashinfer compilation errors. To be fixed.
# "flashinfer_cutlass",
]:
+20
View File
@@ -2733,6 +2733,26 @@ class ServerArgs:
self.tp_size,
], "The expert parallel size must be 1 or the same as the tensor parallel size"
if self.moe_runner_backend == "flashinfer_cutedsl":
assert self.quantization in [
"modelopt_fp4"
], f"Invalid quantization '{self.quantization}'. \nFlashInfer CuteDSL MOE currently supports only: 'modelopt_fp4'."
assert self.ep_size in [
1,
self.tp_size,
], "The expert parallel size must be 1 or the same as the tensor parallel size"
assert self.moe_a2a_backend in [
"none",
"deepep",
], (
f"flashinfer_cutedsl supports moe_a2a_backend='none' (standard path) "
f"or 'deepep' (DeepEP low-latency path), got '{self.moe_a2a_backend}'."
)
self.disable_shared_experts_fusion = True
logger.warning(
"FlashInfer CuteDSL MoE is enabled. --disable-shared-experts-fusion is automatically set."
)
if self.moe_runner_backend == "flashinfer_trtllm":
assert self.quantization in [
"modelopt_fp4",
@@ -0,0 +1,149 @@
"""Backend tests for CuteDSL MoE (FusedMoE + moe_runner, moe_a2a=none).
Exercises the CuteDSL moe_runner path with ModelOpt FP4 by launching a
server with --moe-runner-backend flashinfer_cutedsl.
Two configurations are tested:
- EP=1, TP=4: each GPU holds all experts with TP-sharded intermediate dim
- EP=4, TP=4: each GPU holds 1/4 of experts at full intermediate width,
partial results combined via all-reduce (no A2A dispatch)
Requires 4 GPUs. Run from repo root with:
python -m pytest test/registered/backends/test_deepseek_v3_fp4_cutedsl_moe.py -v -s
Or via the nightly suite:
python test/run_suite.py --hw cuda --suite nightly-4-gpu-b200 --nightly
"""
import unittest
from types import SimpleNamespace
from sglang.srt.utils import kill_process_tree
from sglang.test.ci.ci_register import register_cuda_ci
from sglang.test.few_shot_gsm8k import run_eval as run_eval_few_shot_gsm8k
from sglang.test.test_utils import (
DEFAULT_URL_FOR_TEST,
CustomTestCase,
is_in_ci,
popen_launch_server,
write_github_step_summary,
)
register_cuda_ci(est_time=900, suite="nightly-4-gpu-b200", nightly=True)
FULL_DEEPSEEK_V3_FP4_MODEL_PATH = "nvidia/DeepSeek-V3-0324-FP4"
SERVER_LAUNCH_TIMEOUT = 1000
GSM8K_ACCURACY_THRESHOLD = 0.935
class TestDeepseekV3FP4CuteDSLMoE(CustomTestCase):
"""CuteDSL standard moe_runner path: flashinfer_cutedsl + modelopt_fp4, EP=1."""
@classmethod
def setUpClass(cls):
cls.model = FULL_DEEPSEEK_V3_FP4_MODEL_PATH
cls.base_url = DEFAULT_URL_FOR_TEST
other_args = [
"--tp",
"4",
"--ep",
"1",
"--mem-fraction-static",
"0.75",
"--attention-backend",
"trtllm_mla",
"--moe-runner-backend",
"flashinfer_cutedsl",
"--quantization",
"modelopt_fp4",
"--model-loader-extra-config",
'{"enable_multithread_load": true}',
]
cls.process = popen_launch_server(
cls.model,
cls.base_url,
timeout=SERVER_LAUNCH_TIMEOUT,
other_args=other_args,
)
@classmethod
def tearDownClass(cls):
kill_process_tree(cls.process.pid)
def test_a_gsm8k(
self,
): # Append an "a" to make this test run first (alphabetically) to warm up the server
args = SimpleNamespace(
num_shots=8,
data_path=None,
num_questions=1319,
parallel=1319,
max_new_tokens=512,
host="http://127.0.0.1",
port=int(self.base_url.split(":")[-1]),
)
metrics = run_eval_few_shot_gsm8k(args)
if is_in_ci():
write_github_step_summary(
f"### test_gsm8k (deepseek-v3-fp4-cutedsl-moe)\n"
f'{metrics["accuracy"]=:.3f}\n'
)
self.assertGreater(metrics["accuracy"], GSM8K_ACCURACY_THRESHOLD)
class TestDeepseekV3FP4CuteDSLMoEEP4(CustomTestCase):
"""CuteDSL standard moe_runner path: flashinfer_cutedsl + modelopt_fp4, EP=TP=4."""
@classmethod
def setUpClass(cls):
cls.model = FULL_DEEPSEEK_V3_FP4_MODEL_PATH
cls.base_url = DEFAULT_URL_FOR_TEST
other_args = [
"--tp",
"4",
"--ep",
"4",
"--mem-fraction-static",
"0.75",
"--attention-backend",
"trtllm_mla",
"--moe-runner-backend",
"flashinfer_cutedsl",
"--moe-a2a-backend",
"none",
"--quantization",
"modelopt_fp4",
"--model-loader-extra-config",
'{"enable_multithread_load": true}',
]
cls.process = popen_launch_server(
cls.model,
cls.base_url,
timeout=SERVER_LAUNCH_TIMEOUT,
other_args=other_args,
)
@classmethod
def tearDownClass(cls):
kill_process_tree(cls.process.pid)
def test_a_gsm8k(self):
args = SimpleNamespace(
num_shots=8,
data_path=None,
num_questions=1319,
parallel=1319,
max_new_tokens=512,
host="http://127.0.0.1",
port=int(self.base_url.split(":")[-1]),
)
metrics = run_eval_few_shot_gsm8k(args)
if is_in_ci():
write_github_step_summary(
f"### test_gsm8k (deepseek-v3-fp4-cutedsl-moe-ep4)\n"
f'{metrics["accuracy"]=:.3f}\n'
)
self.assertGreater(metrics["accuracy"], GSM8K_ACCURACY_THRESHOLD)
if __name__ == "__main__":
unittest.main()
+605 -146
View File
@@ -1,18 +1,22 @@
# SPDX-License-Identifier: Apache-2.0
import unittest
from typing import Callable
import torch
from flashinfer import fp4_quantize, scaled_fp4_grouped_quantize
from torch.nn import functional as F
from sglang.jit_kernel.nvfp4 import scaled_fp4_quant
from sglang.srt.layers.activation import SiluAndMul
from sglang.srt.layers.moe.flashinfer_cutedsl_moe import flashinfer_cutedsl_moe_masked
from sglang.srt.layers.moe.topk import TopKConfig, select_experts
from sglang.test.ci.ci_register import register_cuda_ci
register_cuda_ci(est_time=20, suite="stage-c-test-4-gpu-b200")
try:
from flashinfer import CuteDslMoEWrapper
from flashinfer.cute_dsl.utils import convert_sf_to_mma_layout
except ImportError:
CuteDslMoEWrapper = None
convert_sf_to_mma_layout = None
register_cuda_ci(est_time=300, suite="stage-c-test-4-gpu-b200")
SKIP_TEST = torch.cuda.get_device_capability() < (10, 0)
SKIP_REASON = "Nvfp4 Requires compute capability of 10 or above."
@@ -78,6 +82,312 @@ def break_fp4_bytes(a, dtype):
return values.reshape(m, n * 2).to(dtype=dtype)
def _interleave_w13_halves(
x: torch.Tensor, group_size: int = 64, dim: int = -1
) -> torch.Tensor:
"""Interleave the two logical W13 halves for the CuteDSL wrapper layout."""
sizes = x.size()
dim = dim % x.dim()
assert sizes[dim] % (group_size * 2) == 0
prev_sizes = sizes[:dim]
post_sizes = sizes[dim + 1 :]
x = x.view(*prev_sizes, 2, sizes[dim] // (group_size * 2), group_size, *post_sizes)
x = x.transpose(dim, dim + 1).contiguous().view(*sizes)
return x
def _create_cutedsl_wrapper_tensors(
num_tokens: int,
hidden_size: int,
intermediate_size: int,
num_experts: int,
top_k: int,
device: str = "cuda",
seed: int = 42,
):
"""Create quantized tensors for CuteDslMoEWrapper.run() (MMA layout, same as production).
Returns quantized inputs for the wrapper **and** the original bf16 weights
needed to compute a numerical reference. Scale values (w1_alpha, w2_alpha,
fc2_input_scale) are derived from weight magnitudes so that scale-contract
bugs are caught.
"""
assert CuteDslMoEWrapper is not None and convert_sf_to_mma_layout is not None
torch.manual_seed(seed)
sf_vec_size = 16
x_bf16 = (
torch.randn(num_tokens, hidden_size, dtype=torch.bfloat16, device=device) / 10
)
a1_gs = torch.tensor([1.0], device=device, dtype=torch.float32)
x_quantized, x_sf = fp4_quantize(
x_bf16,
global_scale=a1_gs,
sf_vec_size=sf_vec_size,
is_sf_swizzled_layout=False,
)
x_sf = x_sf.unsqueeze(-1)
router_logits = torch.randn(num_tokens, num_experts, device=device)
routing_weights = F.softmax(router_logits, dim=1, dtype=torch.float)
routing_weights, selected_experts = torch.topk(routing_weights, top_k, dim=-1)
routing_weights = routing_weights / routing_weights.sum(dim=-1, keepdim=True)
routing_weights = routing_weights.float()
selected_experts = selected_experts.to(torch.int32)
# --- GEMM1 weights ---
w1_bf16 = (
torch.randn(
num_experts,
2 * intermediate_size,
hidden_size,
dtype=torch.bfloat16,
device=device,
)
/ 10
)
w1_bf16_interleaved = _interleave_w13_halves(w1_bf16, group_size=64, dim=1)
w1_amax = w1_bf16.abs().amax(dim=(1, 2)).to(torch.float32)
w1_gs = FLOAT8_E4M3_MAX * FLOAT4_E2M1_MAX / w1_amax.mean()
w1_gs = w1_gs.unsqueeze(0)
w1_flat = w1_bf16_interleaved.view(num_experts * 2 * intermediate_size, hidden_size)
w1_q_flat, w1_sf_flat = fp4_quantize(
w1_flat,
global_scale=w1_gs,
sf_vec_size=sf_vec_size,
is_sf_swizzled_layout=True,
)
w1_q = w1_q_flat.view(num_experts, 2 * intermediate_size, hidden_size // 2)
w1_weight_sf = convert_sf_to_mma_layout(
w1_sf_flat,
m=2 * intermediate_size,
k=hidden_size,
num_groups=num_experts,
sf_vec_size=sf_vec_size,
)
w1_alpha = 1.0 / (a1_gs * w1_gs).expand(num_experts)
# --- GEMM2 weights ---
w2_bf16 = (
torch.randn(
num_experts,
hidden_size,
intermediate_size,
dtype=torch.bfloat16,
device=device,
)
/ 10
)
w2_amax = w2_bf16.abs().amax(dim=(1, 2)).to(torch.float32)
w2_gs = FLOAT8_E4M3_MAX * FLOAT4_E2M1_MAX / w2_amax.mean()
w2_gs = w2_gs.unsqueeze(0)
w2_flat = w2_bf16.view(num_experts * hidden_size, intermediate_size)
w2_q_flat, w2_sf_flat = fp4_quantize(
w2_flat,
global_scale=w2_gs,
sf_vec_size=sf_vec_size,
is_sf_swizzled_layout=True,
)
w2_q = w2_q_flat.view(num_experts, hidden_size, intermediate_size // 2)
w2_weight_sf = convert_sf_to_mma_layout(
w2_sf_flat,
m=hidden_size,
k=intermediate_size,
num_groups=num_experts,
sf_vec_size=sf_vec_size,
)
fc2_input_scale = FLOAT8_E4M3_MAX * FLOAT4_E2M1_MAX / w2_amax.mean()
fc2_input_scale = fc2_input_scale.unsqueeze(0)
w2_alpha = 1.0 / (fc2_input_scale * w2_gs).expand(num_experts)
return {
"x": x_quantized,
"x_sf": x_sf,
"x_bf16": x_bf16,
"token_selected_experts": selected_experts,
"token_final_scales": routing_weights,
"w1_weight": w1_q,
"w1_weight_sf": w1_weight_sf,
"w1_weight_bf16": w1_bf16,
"w1_alpha": w1_alpha,
"fc2_input_scale": fc2_input_scale,
"w2_weight": w2_q,
"w2_weight_sf": w2_weight_sf,
"w2_weight_bf16": w2_bf16,
"w2_alpha": w2_alpha,
# Global scales needed by _quantize_local_expert_weights
"a1_gs": a1_gs,
"w1_gs": w1_gs,
"w2_gs": w2_gs,
}
def _quantize_local_expert_weights(
w1_bf16_local: torch.Tensor,
w2_bf16_local: torch.Tensor,
a1_gs: torch.Tensor,
w1_gs: torch.Tensor,
w2_gs: torch.Tensor,
fc2_input_scale: torch.Tensor,
):
"""Independently quantize and MMA-convert a local expert weight shard.
Mirrors the per-rank weight preprocessing that happens during model loading
in production (each rank holds [num_local_experts, ...] bf16 weights,
quantizes them, and calls convert_sf_to_mma_layout with
num_groups=num_local_experts).
"""
sf_vec_size = 16
num_local_experts = w1_bf16_local.shape[0]
intermediate_size_2x = w1_bf16_local.shape[1]
hidden_size = w1_bf16_local.shape[2]
intermediate_size = w2_bf16_local.shape[2]
# GEMM1: interleave -> quantize -> MMA layout
w1_interleaved = _interleave_w13_halves(w1_bf16_local, group_size=64, dim=1)
w1_flat = w1_interleaved.view(num_local_experts * intermediate_size_2x, hidden_size)
w1_q_flat, w1_sf_flat = fp4_quantize(
w1_flat,
global_scale=w1_gs,
sf_vec_size=sf_vec_size,
is_sf_swizzled_layout=True,
)
w1_q = w1_q_flat.view(num_local_experts, intermediate_size_2x, hidden_size // 2)
w1_sf = convert_sf_to_mma_layout(
w1_sf_flat,
m=intermediate_size_2x,
k=hidden_size,
num_groups=num_local_experts,
sf_vec_size=sf_vec_size,
)
w1_alpha = 1.0 / (a1_gs * w1_gs).expand(num_local_experts)
# GEMM2: quantize -> MMA layout
w2_flat = w2_bf16_local.view(num_local_experts * hidden_size, intermediate_size)
w2_q_flat, w2_sf_flat = fp4_quantize(
w2_flat,
global_scale=w2_gs,
sf_vec_size=sf_vec_size,
is_sf_swizzled_layout=True,
)
w2_q = w2_q_flat.view(num_local_experts, hidden_size, intermediate_size // 2)
w2_sf = convert_sf_to_mma_layout(
w2_sf_flat,
m=hidden_size,
k=intermediate_size,
num_groups=num_local_experts,
sf_vec_size=sf_vec_size,
)
w2_alpha = 1.0 / (fc2_input_scale * w2_gs).expand(num_local_experts)
return {
"w1_weight": w1_q,
"w1_weight_sf": w1_sf,
"w1_alpha": w1_alpha,
"w2_weight": w2_q,
"w2_weight_sf": w2_sf,
"w2_alpha": w2_alpha,
}
def _run_wrapper(wrapper, tensors, **overrides):
"""Call wrapper.run() with the standard 11-arg dict from _create_cutedsl_wrapper_tensors."""
kwargs = dict(
x=tensors["x"],
x_sf=tensors["x_sf"],
token_selected_experts=tensors["token_selected_experts"],
token_final_scales=tensors["token_final_scales"],
w1_weight=tensors["w1_weight"],
w1_weight_sf=tensors["w1_weight_sf"],
w1_alpha=tensors["w1_alpha"],
fc2_input_scale=tensors["fc2_input_scale"],
w2_weight=tensors["w2_weight"],
w2_weight_sf=tensors["w2_weight_sf"],
w2_alpha=tensors["w2_alpha"],
)
kwargs.update(overrides)
return wrapper.run(**kwargs)
def _quant_dequant_fp4_reference(
tensor: torch.Tensor,
global_scale: torch.Tensor,
sf_vec_size: int = 16,
) -> torch.Tensor:
"""Simulate FP4 quant-dequant roundtrip for reference computation."""
from flashinfer.fp4_quantization import e2m1_and_ufp8sf_scale_to_float
tensor_bf16 = tensor.to(torch.bfloat16)
fp4_packed, sf = fp4_quantize(
tensor_bf16,
global_scale=global_scale,
sf_vec_size=sf_vec_size,
is_sf_swizzled_layout=False,
)
sf_uint8 = sf.view(torch.uint8).reshape(-1)
dequantized = e2m1_and_ufp8sf_scale_to_float(
fp4_packed.cpu(),
sf_uint8.cpu(),
(1.0 / global_scale).cpu(),
sf_vec_size=sf_vec_size,
ufp8_type=1,
is_sf_swizzled_layout=False,
).to(tensor.device)
return dequantized.float()
def _compute_reference_moe_fp4(
hidden_states: torch.Tensor,
gemm1_weights: torch.Tensor,
gemm2_weights: torch.Tensor,
token_selected_experts: torch.Tensor,
token_final_scales: torch.Tensor,
num_experts: int,
top_k: int,
hidden_size: int,
intermediate_size: int,
fc2_input_scale: torch.Tensor,
) -> torch.Tensor:
"""Pure-PyTorch MoE reference using bf16 weights (pre-interleave layout).
gemm1_weights is [num_experts, 2*intermediate_size, hidden_size] with the
*original* (un-interleaved) layout: first half = linear, second half = gate.
"""
device = hidden_states.device
num_tokens = hidden_states.shape[0]
hidden_states = hidden_states.float()
gemm1_weights = gemm1_weights.float()
gemm2_weights = gemm2_weights.float()
output = torch.zeros(num_tokens, hidden_size, dtype=torch.float32, device=device)
for token_idx in range(num_tokens):
token_input = hidden_states[token_idx : token_idx + 1]
for k in range(top_k):
expert_idx = token_selected_experts[token_idx, k].item()
scale = token_final_scales[token_idx, k].item()
if expert_idx < 0 or expert_idx >= num_experts:
continue
w1 = gemm1_weights[expert_idx]
gemm1_out = token_input @ w1.T
linear = gemm1_out[:, :intermediate_size]
gate = gemm1_out[:, intermediate_size:]
swiglu_out = F.silu(gate) * linear
if fc2_input_scale is not None:
swiglu_out = _quant_dequant_fp4_reference(
swiglu_out, fc2_input_scale, sf_vec_size=16
)
w2 = gemm2_weights[expert_idx]
gemm2_out = swiglu_out @ w2.T
output[token_idx] += scale * gemm2_out.squeeze(0)
return output
def compute_routing(router_logits: torch.Tensor, top_k: int):
routing_weights = torch.softmax(router_logits, dim=1, dtype=torch.float)
routing_weights, selected_experts = torch.topk(routing_weights, top_k, dim=-1)
@@ -109,20 +419,6 @@ def prepare_inputs(
return hidden_states_3d, masked_m, topk_idx, routing_weights
MNK_FACTORS = [
(2, 1024, 1024),
(2, 1024, 1536),
(2, 3072, 1024),
(2, 3072, 1536),
(64, 1024, 1024),
(64, 1024, 1536),
(64, 3072, 1024),
(64, 2048, 1024),
(224, 1024, 1024),
(224, 1024, 1536),
]
# Reference implementation of torch_moe
def torch_moe(a, w1, w2, score, topk, expert_map):
B, D = a.shape
@@ -158,7 +454,7 @@ def torch_moe_nvfp4(a, w1, w2, topk, topk_weight, topk_ids):
if mask.sum():
m = w1[i].shape[0]
assert m % 2 == 0
# Note: w1 and w3 are swapped!
# The first and second W13 halves feed the two SwiGLU branches.
w3_expert, w1_expert = w1[i][m // 2 :, :], w1[i][: m // 2, :]
inter = F.silu(a[mask] @ w1_expert.t()) * (a[mask] @ w3_expert.t())
inter_gs = torch.tensor(1.0).cuda()
@@ -177,128 +473,6 @@ def torch_moe_nvfp4(a, w1, w2, topk, topk_weight, topk_ids):
).sum(dim=1)
def check_moe(
m: int,
n: int,
k: int,
e: int,
topk: int,
dtype: torch.dtype,
moe_impl: Callable,
flip_w13: bool,
):
torch.manual_seed(7)
a = torch.randn((m, k), device="cuda", dtype=dtype) / 10
w1 = torch.randn((e, 2 * n, k), device="cuda", dtype=dtype) / 10
quant_blocksize = 16
round_up = lambda x, y: (x + y - 1) // y * y
sf_w1_2n = round_up(2 * n, 128)
sf_w1_k = round_up(k // quant_blocksize, 4)
w1_blockscale = torch.empty(
(e, sf_w1_2n, sf_w1_k), device="cuda", dtype=torch.float8_e4m3fn
)
w2 = torch.randn((e, k, n), device="cuda", dtype=dtype) / 10
sf_w2_k = round_up(k, 128)
sf_w2_n = round_up(n // quant_blocksize, 4)
w2_blockscale = torch.empty(
(e, sf_w2_k, sf_w2_n), device="cuda", dtype=torch.float8_e4m3fn
)
w1_q = torch.empty((e, 2 * n, k // 2), device="cuda", dtype=torch.uint8)
w2_q = torch.empty((e, k, n // 2), device="cuda", dtype=torch.uint8)
w1_gs = torch.empty((e,), device="cuda", dtype=torch.float32)
w2_gs = torch.empty((e,), device="cuda", dtype=torch.float32)
for expert in range(e):
w1_amax = torch.abs(w1).max().to(torch.float32)
w2_amax = torch.abs(w2).max().to(torch.float32)
w1_gs[expert] = FLOAT8_E4M3_MAX * FLOAT4_E2M1_MAX / w1_amax
w2_gs[expert] = FLOAT8_E4M3_MAX * FLOAT4_E2M1_MAX / w2_amax
w1_q[expert], w1_blockscale[expert] = scaled_fp4_quant(
w1[expert], w1_gs[expert]
)
w2_q[expert], w2_blockscale[expert] = scaled_fp4_quant(
w2[expert], w2_gs[expert]
)
score = torch.randn((m, e), device="cuda", dtype=dtype)
topk_output = select_experts(
hidden_states=a,
router_logits=score,
topk_config=TopKConfig(top_k=topk, renormalize=False),
)
topk_weights, topk_ids, _ = topk_output
a1_gs = torch.ones((e,), device="cuda", dtype=torch.float32)
a2_gs = torch.ones((e,), device="cuda", dtype=torch.float32)
test_output = moe_impl(
a=a,
topk_weights=topk_weights,
topk_ids=topk_ids,
w1_q=w1_q,
w2_q=w2_q,
a1_gs=a1_gs,
w1_blockscale=w1_blockscale,
w1_alphas=(1 / w1_gs),
a2_gs=a2_gs,
w2_blockscale=w2_blockscale,
w2_alphas=(1 / w2_gs),
)
# Reference check:
a_global_scale = (
(FLOAT8_E4M3_MAX * FLOAT4_E2M1_MAX) / torch.amax(a.flatten(), dim=-1)
).to(torch.float32)
a_fp4, a_scale_interleaved = scaled_fp4_quant(a, a_global_scale)
_, m_k = a_fp4.shape
a_in_dtype = dequantize_nvfp4_to_dtype(
a_fp4,
a_scale_interleaved,
a_global_scale,
dtype=a.dtype,
device=a.device,
block_size=quant_blocksize,
)
w1_d = torch.empty((e, 2 * n, k), device="cuda", dtype=dtype)
w2_d = torch.empty((e, k, n), device="cuda", dtype=dtype)
for idx in range(0, e):
w1_d[idx] = dequantize_nvfp4_to_dtype(
w1_q[idx],
w1_blockscale[idx],
w1_gs[idx],
dtype=w1.dtype,
device=w1.device,
block_size=quant_blocksize,
)
w2_d[idx] = dequantize_nvfp4_to_dtype(
w2_q[idx],
w2_blockscale[idx],
w2_gs[idx],
dtype=w2.dtype,
device=w2.device,
block_size=quant_blocksize,
)
if flip_w13:
dim = -2
size = w1_d.size(dim)
assert size % 2 == 0, f"Expected even size in dim {dim}, got {size}"
half = size // 2
# Reorder weight
w1, w3 = w1_d.split(half, dim=dim)
w1_d = torch.cat([w3, w1], dim=dim).contiguous()
torch_output = torch_moe(a_in_dtype, w1_d, w2_d, score, topk, None)
torch.testing.assert_close(torch_output, test_output, atol=1e-1, rtol=1e-1)
class TestFlashinferCutedslMoe(unittest.TestCase):
@unittest.skipIf(SKIP_TEST, SKIP_REASON)
def test_flashinfer_cutedsl_moe_masked(self):
@@ -316,9 +490,6 @@ class TestFlashinferCutedslMoe(unittest.TestCase):
with self.subTest(
bs=bs, hidden_dim=hidden_dim, inter_dim=inter_dim, topk=topk
):
print(
f"Testing with bs={bs}, hidden_dim={hidden_dim}, inter_dim={inter_dim}, topk={topk}"
)
with torch.inference_mode():
torch.manual_seed(42)
device = "cuda"
@@ -476,8 +647,296 @@ class TestFlashinferCutedslMoe(unittest.TestCase):
torch.testing.assert_close(
out_weighted.cpu(), ref_output.cpu(), atol=5e-2, rtol=5e-2
)
print(
f"Test passed with bs={bs}, hidden_dim={hidden_dim}, inter_dim={inter_dim}, topk={topk}"
@unittest.skipIf(SKIP_TEST, SKIP_REASON)
@unittest.skipIf(
CuteDslMoEWrapper is None or convert_sf_to_mma_layout is None,
"CuteDslMoEWrapper / convert_sf_to_mma_layout not available",
)
def test_cutedsl_moe_wrapper_run(self):
"""Call CuteDslMoEWrapper.run() with MMA-layout tensors and verify against reference."""
test_cases = [
# (num_tokens, hidden_size, intermediate_size, num_experts, top_k)
# Minimum dimensions match FlashInfer's test_wrapper_accuracy:
# num_experts >= 256, hidden_size >= 256, intermediate_size >= 512,
# num_tokens >= 128. The CuteDSL GEMM kernels have tile-size
# constraints that make smaller dimensions unreliable.
(128, 256, 512, 256, 2),
(128, 256, 512, 256, 8),
(256, 256, 512, 256, 4),
]
for (
num_tokens,
hidden_size,
intermediate_size,
num_experts,
top_k,
) in test_cases:
with self.subTest(
num_tokens=num_tokens,
hidden_size=hidden_size,
intermediate_size=intermediate_size,
top_k=top_k,
):
tensors = _create_cutedsl_wrapper_tensors(
num_tokens=num_tokens,
hidden_size=hidden_size,
intermediate_size=intermediate_size,
num_experts=num_experts,
top_k=top_k,
)
wrapper = CuteDslMoEWrapper(
num_experts=num_experts,
top_k=top_k,
hidden_size=hidden_size,
intermediate_size=intermediate_size,
use_cuda_graph=False,
)
with torch.no_grad():
out = _run_wrapper(wrapper, tensors)
self.assertEqual(out.shape, (num_tokens, hidden_size))
self.assertEqual(out.dtype, torch.bfloat16)
self.assertFalse(
torch.isnan(out).any().item() or torch.isinf(out).any().item(),
"Output contains NaN or Inf",
)
ref_output = _compute_reference_moe_fp4(
hidden_states=tensors["x_bf16"].float().cuda(),
gemm1_weights=tensors["w1_weight_bf16"].float().cuda(),
gemm2_weights=tensors["w2_weight_bf16"].float().cuda(),
token_selected_experts=tensors["token_selected_experts"],
token_final_scales=tensors["token_final_scales"],
num_experts=num_experts,
top_k=top_k,
hidden_size=hidden_size,
intermediate_size=intermediate_size,
fc2_input_scale=tensors["fc2_input_scale"],
)
out_f32 = out.float()
ref_f32 = ref_output.float()
output_scale = max(ref_f32.std().item(), 0.01)
atol = max(0.1, 3.0 * output_scale)
rtol = 0.85
abs_diff = torch.abs(out_f32 - ref_f32)
rel_diff = abs_diff / (torch.abs(ref_f32) + 1e-8)
within_tol = (abs_diff < atol) | (rel_diff < rtol)
pct_within = within_tol.float().mean().item()
self.assertGreaterEqual(
pct_within,
0.925,
f"Only {pct_within * 100:.2f}% of elements within tolerance "
f"(atol={atol:.4f})",
)
@unittest.skipIf(SKIP_TEST, SKIP_REASON)
@unittest.skipIf(
CuteDslMoEWrapper is None or convert_sf_to_mma_layout is None,
"CuteDslMoEWrapper / convert_sf_to_mma_layout not available",
)
def test_cutedsl_cuda_graph_parity(self):
"""Verify non-graph and cuda_graph wrappers produce identical results.
Also checks both match the pure-PyTorch reference, and that a second
cuda_graph pass reuses buffers deterministically (subsumes the former
cuda_graph_smoke test).
"""
test_cases = [
# (num_tokens, hidden_size, intermediate_size, num_experts, top_k)
(128, 256, 512, 256, 2),
(256, 256, 512, 256, 4),
]
for (
num_tokens,
hidden_size,
intermediate_size,
num_experts,
top_k,
) in test_cases:
with self.subTest(
num_tokens=num_tokens,
hidden_size=hidden_size,
intermediate_size=intermediate_size,
top_k=top_k,
):
tensors = _create_cutedsl_wrapper_tensors(
num_tokens=num_tokens,
hidden_size=hidden_size,
intermediate_size=intermediate_size,
num_experts=num_experts,
top_k=top_k,
)
wrapper_args = dict(
num_experts=num_experts,
top_k=top_k,
hidden_size=hidden_size,
intermediate_size=intermediate_size,
)
wrapper_no_graph = CuteDslMoEWrapper(
**wrapper_args, use_cuda_graph=False
)
wrapper_graph = CuteDslMoEWrapper(
**wrapper_args,
use_cuda_graph=True,
max_num_tokens=num_tokens,
)
with torch.no_grad():
out_no_graph = _run_wrapper(wrapper_no_graph, tensors)
out_graph = _run_wrapper(wrapper_graph, tensors)
out_graph2 = _run_wrapper(wrapper_graph, tensors)
torch.testing.assert_close(
out_no_graph,
out_graph,
atol=1e-2,
rtol=1e-2,
msg="non-graph vs cuda_graph wrapper outputs diverge",
)
torch.testing.assert_close(
out_graph,
out_graph2,
atol=1e-5,
rtol=1e-5,
msg="second cuda_graph pass should reuse buffers identically",
)
ref_output = _compute_reference_moe_fp4(
hidden_states=tensors["x_bf16"].float().cuda(),
gemm1_weights=tensors["w1_weight_bf16"].float().cuda(),
gemm2_weights=tensors["w2_weight_bf16"].float().cuda(),
token_selected_experts=tensors["token_selected_experts"],
token_final_scales=tensors["token_final_scales"],
num_experts=num_experts,
top_k=top_k,
hidden_size=hidden_size,
intermediate_size=intermediate_size,
fc2_input_scale=tensors["fc2_input_scale"],
)
out_f32 = out_graph.float()
ref_f32 = ref_output.float()
output_scale = max(ref_f32.std().item(), 0.01)
atol = max(0.1, 3.0 * output_scale)
rtol = 0.85
abs_diff = torch.abs(out_f32 - ref_f32)
rel_diff = abs_diff / (torch.abs(ref_f32) + 1e-8)
within_tol = (abs_diff < atol) | (rel_diff < rtol)
pct_within = within_tol.float().mean().item()
self.assertGreaterEqual(
pct_within,
0.925,
f"graph vs reference: only {pct_within * 100:.2f}% within tol",
)
@unittest.skipIf(SKIP_TEST, SKIP_REASON)
@unittest.skipIf(
CuteDslMoEWrapper is None or convert_sf_to_mma_layout is None,
"CuteDslMoEWrapper / convert_sf_to_mma_layout not available",
)
def test_cutedsl_ep_sharded_allreduce(self):
"""Verify EP-sharded execution: partial outputs from EP ranks sum to full result.
Simulates the EP=TP all-reduce pattern used by the CuteDSL moe_runner when
ep_size > 1 and moe_a2a_backend=none. Each "rank" runs a wrapper with
num_local_experts < num_experts and a corresponding local_expert_offset,
receiving only the local slice of weights/scales/alphas — matching the
real runtime contract where each rank holds only its own expert partition.
The partial outputs are summed (simulating tensor_model_parallel_all_reduce)
and compared against a single wrapper processing all experts.
"""
test_cases = [
# (num_tokens, hidden_size, intermediate_size, num_experts, top_k, ep_size)
# Dimensions match FlashInfer's minimum wrapper requirements.
(128, 256, 512, 256, 2, 2),
(128, 256, 512, 256, 2, 4),
(128, 256, 512, 256, 8, 8),
]
for (
num_tokens,
hidden_size,
intermediate_size,
num_experts,
top_k,
ep_size,
) in test_cases:
with self.subTest(
num_tokens=num_tokens,
hidden_size=hidden_size,
intermediate_size=intermediate_size,
top_k=top_k,
ep_size=ep_size,
):
assert num_experts % ep_size == 0
num_local_experts = num_experts // ep_size
tensors = _create_cutedsl_wrapper_tensors(
num_tokens=num_tokens,
hidden_size=hidden_size,
intermediate_size=intermediate_size,
num_experts=num_experts,
top_k=top_k,
)
# Full-expert baseline (EP=1): all experts on one "rank"
wrapper_full = CuteDslMoEWrapper(
num_experts=num_experts,
top_k=top_k,
hidden_size=hidden_size,
intermediate_size=intermediate_size,
use_cuda_graph=False,
)
with torch.no_grad():
out_full = _run_wrapper(wrapper_full, tensors)
# EP-sharded: each rank independently quantizes its local
# bf16 weight shard and calls convert_sf_to_mma_layout with
# num_groups=num_local_experts — matching the real per-rank
# weight preprocessing in the CuteDSL moe_runner path.
accumulated = torch.zeros_like(out_full)
for rank in range(ep_size):
lo = rank * num_local_experts
hi = lo + num_local_experts
local_tensors = _quantize_local_expert_weights(
w1_bf16_local=tensors["w1_weight_bf16"][lo:hi],
w2_bf16_local=tensors["w2_weight_bf16"][lo:hi],
a1_gs=tensors["a1_gs"],
w1_gs=tensors["w1_gs"],
w2_gs=tensors["w2_gs"],
fc2_input_scale=tensors["fc2_input_scale"],
)
wrapper_shard = CuteDslMoEWrapper(
num_experts=num_experts,
top_k=top_k,
hidden_size=hidden_size,
intermediate_size=intermediate_size,
use_cuda_graph=False,
num_local_experts=num_local_experts,
local_expert_offset=lo,
)
with torch.no_grad():
partial = _run_wrapper(wrapper_shard, tensors, **local_tensors)
accumulated += partial
torch.testing.assert_close(
out_full,
accumulated,
atol=1e-2,
rtol=1e-2,
msg=(
f"EP-sharded all-reduce mismatch "
f"(ep_size={ep_size}, tokens={num_tokens})"
),
)